An unemployed antiques enthusiast has stumbled on a rare Renaissance painting which could be worth £250,000.

Mark Lawrence from Tilehurst, who collects and sells antiques when he can, bought the work of art for £350 from an antique shop in Windsor.

The little painting on copper – of St Jerome in the Wilderness – was named incorrectly on the frame as a work by Palma Vecchio.

But in fact it is a lost work by Vecchio’s nephew Palma Giovane, an Italian master from the Renaissance era.

The 21-year-old did not buy it at once but went back later and saw it was still there.

He said: “I knew it was a beautiful painting, but I didn’t know how old it was or anything about the artist.”

Mr Lawrence, of The Meadway, got his professional art restorer friend to clean it then took it to the Museum of Reading at one of its regular Thursday afternoon surgeries – a kind of Antiques Roadshow when experts identify objects brought in by members of the public.

Elaine Blake, curator of paintings at the museum, said: “We are normally brought things like flints and fossils.

“It was really thrilling to be brought this painting. It was clear that it was very good, a really superb painting but I couldn’t be sure whether it was a really good Victorian copy or an original.”

The museum does not authenticate items but can provide information and offer advice on how to get items identified reliably.

Mr Lawrence then went to the National Gallery where the experts identified it as a “lost” work by Palma Giovane.

He said: “They were able to trace references to this work called St Jerome in the Wilderness which had apparently been lost.”

Mr Lawrence said Bonhams the auctioneers had suggested the work might be worth as much as £250,000, because it was a painting that had been lost.

The work by the Italian master, who painted in the mannerist style and succeeded Tintoretto as the leading painter in Venice in 1594, is believed to have been painted in 1595.

It will be returning to London soon so it can be studied by experts.

Mr Lawrence added: “It may well be worth a great deal of money but I am just mad enough to keep it.”

However, he will not be keeping it at home – where he has been burgled twice – but is storing it in a bank until he decides on its future.